Sewing machine

ABSTRACT

A sewing machine includes a plurality of types of embroidery frames having respective holding parts holding workpiece cloth, the holding parts having forms differing from one type of embroidery frame to another, a carriage to which one of the embroidery frames is selectively attached, the carriage being configured to transfer the embroidery frame, a projector configured to project an image onto the workpiece cloth, a detector configured to detect a type of the embroidery frame attached to the carriage, a storage unit configured to store frame information set for every type of embroidery frame, a setting unit configured to read the frame information according to result of detection by the detector and to set a projection region for an image to be projected, based on the frame information, and a control unit configured to control the projector so that the projector projects the image onto the set projection region.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2014-053442 filed on Mar. 17, 2014, the entire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a sewing machine provided with a projector which projects an image onto a workpiece cloth held on an embroidery frame.

2. Related Art

Embroidery sewing machines have conventionally been known which are provided with projectors. In these embroidery sewing machines, the projectors can project an image of embroidery pattern simulating a completed pattern onto a workpiece cloth held on an embroidery frame.

SUMMARY

There is a plurality of types of embroidery frames differing in the size and the shape. Accordingly, projection conditions such as a size of projection region and projection position need to be adjusted according to a type of embroidery frame. However, the relationship between the type of embroidery pattern and the projection conditions has not been considered in the conventional embroidery sewing machines.

Therefore, an object of the disclosure is to provide a sewing machine which is provided with a projector projecting an image onto the workpiece cloth held on the embroidery frame, to which one of a plurality of types of embroidery frames is selectively attachable and wherein the projector can project an image onto the workpiece cloth properly according to the size and the shape of the embroidery frame.

The disclosure provides a sewing machine including a plurality of types of embroidery frames having respective holding parts which hold a workpiece cloth, the holding parts having forms differing from one type of embroidery frame to another, a carriage to which one of the embroidery frames is selectively attached, the carriage being configured to transfer the embroidery frame attached thereto, a projector configured to project an image onto the workpiece cloth held on the holding part of the embroidery frame attached to the carriage, a detector configured to detect a type of the embroidery frame attached to the carriage, a storage unit configured to store frame information set for every type of embroidery frame, a setting unit configured to read the frame information from the storage unit according to a result of detection by the detector and to set a projection region for an image to be projected by the projector, based on the frame information, and a control unit configured to control the projector so that the projector projects the image onto the projection region set by the setting unit.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a perspective view of a sewing machine according to one embodiment as viewed from obliquely above at the front;

FIG. 2 is a perspective view of the sewing machine as viewed from obliquely above at the right side;

FIG. 3 is a left side view of the sewing machine;

FIG. 4 is a block diagram showing an electrical arrangement of the sewing machine;

FIG. 5 is a plan view of an embroidery frame A attached to the carriage located at a specified position;

FIG. 6 is also a plan view of an embroidery frame B attached to the carriage located at the specified position;

FIG. 7 is also a plan view of an embroidery frame C attached to the carriage located at the specified position;

FIGS. 8A, 8B and 8C show the positional relationships between a detector and a detected object with respect to the embroidery frames A, B and C, respectively;

FIG. 9 is a conceptual diagram showing the contents of a ROM and a RAM;

FIG. 10 shows an example of frame information;

FIG. 11 shows the size and center position of a sewable region relative to a projectable region with respect to each one of the embroidery frames;

FIG. 12 is a flowchart showing processing of control by a control device;

FIGS. 13A and 13B illustrate images projected from the projector onto the embroidery frame A, showing the state in which an image representing a sewable region is projected onto the workpiece cloth and the state in which an image representing a sewable region and an image representing an embroidery pattern are projected onto the workpiece cloth, respectively;

FIGS. 14A and 14B illustrate images projected from the projector onto the embroidery frame B, showing the state in which an image representing a sewable region is projected onto the workpiece cloth and the state in which an image representing a sewable region and an image representing an embroidery pattern are projected onto the workpiece cloth, respectively; and

FIGS. 15A and 15B illustrate images projected from the projector onto the embroidery frame C, showing the state in which an image representing a sewable region is projected onto the workpiece cloth and the state in which an image representing a sewable region and an image representing an embroidery pattern are projected onto the workpiece cloth, respectively.

DETAILED DESCRIPTION

An embodiment will be described with reference to the drawings. Referring to FIGS. 1 to 3, a sewing machine 10 of the embodiment is a multi-needle sewing machine having six needle bars 21 and includes two legs 11, a pillar 12, an arm 13, a cylinder bed 14, a carriage 15 and a needle bar case 20. In the following description, the side where a user is located relative to the sewing machine 10 will be referred to as “front” of the sewing machine 10. The side located opposite the front will be referred to as “rear.” The direction in which the legs 11 are opposed to each other is a right-left direction of the sewing machine 10. The direction perpendicular to the right-left direction is a front-back direction of the sewing machine 10. The direction perpendicular to the right-left direction and the front-back direction is an up-down direction. The right-left direction correspond to an X direction and the front-back direction corresponds to a Y direction.

The right and left legs 11 support the entire sewing machine 10. The pillar 12 extends upward from rear ends of the legs 11 as shown in FIG. 3. The arm 13 extends frontward from an upper end of the pillar 12. The cylinder bed 14 extends frontward from a lower end of the pillar 12. The carriage 15 is mounted on upper sides of the legs 11. The carriage 15 includes a Y-direction carriage 151 and an X-direction carriage 152 as shown in FIGS. 5 to 7. The Y-direction carriage 151 extends in the right-left direction and is moved in the Y direction (the front-back direction) by a Y-axis drive mechanism (not shown) provided in interiors of the legs 11. The X-direction carriage 152 is provided on a front of the Y-direction carriage 151. The X-direction carriage 152 is moved in the X direction (the right-left direction) by an X-axis drive mechanism (not shown) provided in an interior of the Y-direction carriage 151. The X-axis drive mechanism is driven by an X-axis motor 16 (see FIG. 4). The X-direction carriage 152 is moved in the Y direction together with the Y-direction carriage 151.

The needle bar case 20 supports the six needle bars 21 so that the needle bars 21 are movable in the up-down direction. The needle bars 21 are arranged in the right-left direction so as to extend in the up-down direction. The needle bars 21 have lower ends to which needles 22 are attached respectively. The needle bar case 20 also has six pressers 201, six thread take-up levers 23 and six thread tensioners 24. The pressers 201 are mounted on a lower part of the needle bar case 20 and arranged in the right-left direction so as to correspond to the needle bars 21 respectively. The thread take-up levers 23 are mounted on the upper front of the needle bar case 20 and arranged in the right-left direction so as to correspond to the needle bars 21 respectively. The thread take-up levers 23 are configured to be movable up and down in synchronization with the needle bars 21 respectively. The thread tensioners 24 are mounted on an upper part of the needle bar case 20 to adjust thread tensions of needle threads which will be described later.

The sewing machine 10 further includes a pair of right and left spool holder bases 25 and a thread guide mechanism 26. The spool holder bases 25 and the thread guide mechanism 26 are mounted on the rear top of the arm 13 and located in the rear of the thread tensioners 24. Thread spools (not shown) on which respective threads (hereinafter, “needle threads”) are wound are placed on the spool holder bases 25. Three thread spools in each one of the spool holder bases 25, six thread spools in total are placed on the spool holder bases 25. The thread spools are arranged in a lengthwise direction of each spool holder base 25. It is assumed that the needle threads wound on the respective thread spools differ from one another in color. The needle threads drawn from the respective thread spools are passed through the thread guide mechanism 26, the thread tensioners 24 and the thread take-up levers 23 to be supplied through needle eyes (not shown) of the corresponding needles 22.

The cylinder bed 14 has a needle plate 27, which is mounted on an upper surface of the distal end thereof. The needle plate 27 has a needle hole (not shown) formed therethrough. The needles 22 attached to the respective needle bars 21 are insertable through the needle hole. A needle location refers to a location of the needle bar 21 having the needle 22 located directly above the needle hole of the needle plate 27. A rotating hook (not shown) is provided below the needle plate 27 in the interior of the cylinder bed 14. A bobbin on which a bobbin thread is wound is attached to the rotating hook although not shown.

A needle bar selecting mechanism (not shown) is provided in the interior of the arm 13. The needle bar selecting mechanism moves the needle bar case 20 in the right-left direction to locate any one of the needle bars 21 at the needle location. Thus, one of the needle bars 21 is selected with the result that a thread color of the needle thread of an embroidery pattern to be sewn on a workpiece cloth is changed. The needle bar 21 located at the needle location is moved up and down together with the corresponding thread take-up lever 23 by a sewing machine motor 28 (see FIG. 4) mounted in the pillar 12. The embroidery pattern is sewn on the workpiece cloth held on, for example, an embroidery frame W in cooperation of the needle bar 21, the thread take-up lever 23 and the rotating hook.

The sewing machine 10 is provided with a plurality of types of embroidery frames which is selectively attachable. More specifically, the sewing machine 10 is provided with three types of embroidery frames including an embroidery frame A (see FIG. 5), an embroidery frame B (see FIG. 6) and an embroidery frame C (see FIG. 7). The embroidery frames A, B and C differ in the form from one another. In this case, the embroidery frames A, B and C differ in the size and shape from one another. The sewing machine 10 may be provided with embroidery frames differing in the form from the embroidery frames A, B and C. An embroidery frame W will hereinafter refer to any one of the embroidery patterns A, B and C. The embroidery pattern W attached to the carriage 15 is moved in the X direction with movement of the X-direction carriage 152 and is moved in the Y direction with movement of the Y-direction carriage 151. The embroidery frame W holds a workpiece cloth according to the size thereof. The workpiece cloth held on the embroidery frame W is moved in the X direction and the Y direction with movement of the embroidery frame W.

The embroidery frame W has a previously set sewable region. The sewable region refers to a region where an embroidery pattern can be sewn on the workpiece cloth and more specifically a rectangular region set inside a holding part of the embroidery frame W, as will be described in detail later.

A first frame holder 50 is attached to the X-direction carriage 152 as shown in FIG. 5. The first frame holder 50 includes a holder body 51, a fixed arm 52, a moving arm 53 and a sliding part 54. The holder body 51 is formed to extend in the X direction from the right end side to the left end side of the Y-direction carriage 151. The holder body 51 is fixed to the X-direction carriage 152 by a screw (not shown). The fixed arm 52 protrudes forward from the right end side of the holder body 51. The fixed arm 52 is fixed to the holder body 51 by a screw 55. The moving arm 53 protrudes forward from the left end side of the holder body 51 so that the fixed and moving arms 52 and 53 are substantially bilaterally symmetric. The sliding part 54 extends rightward from a right end of the moving arm 53 along the holder body 51. The moving arm 53 and the sliding part 54 are movable together.

The sliding part 54 is formed with an elongate hole 541 extending in the X direction. A plurality of pins 511 are inserted through the elongate hole 541 to be fixed to the holder body 51. The holder body 51 also has an elongate hole 512 which is formed through a left end side thereof so as to extend in the X direction, as shown in FIGS. 5 and 6. An adjusting screw 531 is rotatably supported in the rear of the moving arm 53 although not shown in detail. The adjusting screw 531 adjusts X-direction positions of the moving arm 53 and the sliding part 54. The adjusting screw 531 is moved in the X direction together with the moving arm 53. The adjusting screw 531 includes a lower portion formed with a threaded part (not shown) which is inserted through the elongate hole 512 to be threadingly engaged with a screw hole formed in an auxiliary plate (not shown) which is disposed so as to abut against the underside of the holder body 51. The auxiliary plate is locked by the holder body 51 so as to be prevented from rotation even when the adjusting screw 531 is turned. The auxiliary plate is moved in the X direction together with the adjusting screw 531, the moving arm 53 and the sliding part 54.

As the result of the foregoing construction, the moving arm 53 and the sliding part 54 are movable in the X direction relative to the holder body 51 when the adjusting screw 531 is loosened. On the other hand, the moving arm 53 and the sliding part 54 are fixed to the holder body 51 when the adjusting screw 531 is tightened. Thus, a plurality of types of embroidery frames W is selectively attachable to the carriage 15 by suitably adjusting an X-direction distance (dimension) between the fixed arm 52 and the moving arm 53.

The embroidery frame A includes an inner frame 61, an outer frame 62 and attaching parts 63 and 64 as shown in FIG. 5. The inner and outer frames 61 and 62 form a first holding part 60. Each one of the inner and outer frames 61 and 62 is formed by rounding corners of a rectangle long in the X direction as a whole into a frame shape. Inside the inner frame 61 is set a sewable region Qa expressed by 180 mm×130 mm in the respective X and Y directions. The inner frame 61 is fitted with an inner periphery of the outer frame 62, so that a workpiece cloth 101 is held between the inner and outer frames 61 and 62. The attaching parts 64 and 63 comprise flat plate members and extend outward from right and left ends of the inner frame 61 respectively. The left attaching part 63 is attached to a distal end of the moving arm 53, and the right attaching part 64 is attached to a distal end of the fixed arm 52. The embroidery frame A is thus attached to the carriage 15.

The embroidery frame B includes an inner frame 71, an outer frame 72 and attaching parts 73 and 74 as shown in FIG. 6. The inner and outer frames 71 and 72 form a second holding part 60. Each one of the inner and outer frames 71 and 72 is formed into substantially elliptic frame shape long in the X direction as a whole. Inside the inner frame 71 is set a sewable region Qb expressed by 60 mm×40 mm in the respective X and Y directions. The inner frame 71 is fitted with an inner periphery of the outer frame 72, so that a workpiece cloth 101 is held between the inner and outer frames 71 and 72. The attaching parts 74 and 73 comprise respective flat plate members and extend outward from right and left ends of the inner frame 71. The left attaching part 73 is attached to a distal end of the moving arm 53, and the right attaching part 74 is attached to a distal end of the fixed arm 52. The embroidery frame B is thus attached to the carriage 15.

The embroidery frame C includes an inner frame 91, an outer frame 92 and an attaching part 80 as shown in FIG. 7. The inner and outer frames 91 and 92 form a third holding part 90. Each one of the inner and outer frames 91 and 92 is formed into a circular frame shape. Inside the inner frame 71 is set a sewable region Qc expressed by 25 mm×25 mm in the respective X and Y directions. The inner frame 91 is fitted with an inner periphery of the outer frame 92, so that a workpiece cloth 101 is held between the inner and outer frames 91 and 92. The attaching part 80 comprises a flat plate member and extends rearward from a rear end of the outer frame 92. The attaching part 80 has a rear end which is attached to the second frame holder 82 fixed to the X-direction carriage 152 by the screw although the attaching manner is not shown in detail. More specifically, when the above-described first frame holder 50 is attached to the X-direction carriage 152, the first frame holder 50 is detached from the X-direction carriage 152 and the second frame holder 82 is attached to the X-direction carriage 152 to be fixed by the screw instead. Thus, the embroidery frame C is attached to the carriage 15.

The sewing machine 10 includes a detector 18 which detects a type of the embroidery frame W attached to the carriage 15. The detector 18 comprises a rotary potentiometer and is mounted on the X-direction carriage 152 so as to be located at the moving arm 53 side, as shown in FIGS. 5 to 7. The detector 18 includes a shaft 181 and a detection lever 182 both of which are formed integrally with each other, as shown in FIGS. 8A to 8C. The detection lever 182 is rotatable about a center of the shaft 181. The detection lever 182 is biased clockwise by a torsion spring (not shown) surrounding the shaft 181. The detection lever 182 has a distal end from which a small columnar pin 183 formed integrally with the shaft 181 protrudes forward. The detector 18 is electrically connected to a control device 31 which will be described later. A resistance value of a variable resistance incorporated in the detector 18 varies when the detection lever 182 is rotated. The control device 31 detects a variation in the resistance value as a change in a voltage value, thereby detecting a rotational angle of the detection lever 182.

The sliding part 54 of the first frame holder 50 is provided with an object 56 to be detected as shown in FIGS. 8A and 8B. The object 56 is formed substantially into the shape of a bar extending in the X direction. The object 56 includes a first detected part 561 and a second detected part 562 both of which have different height positions. More specifically, the second detected part 562 is located at a higher position than the first detected part 561. A connecting part 563 located between the first and second detected parts 561 and 562 is inclined and connects between the first and second detected parts 561 and 562. The object 56 is located directly above the pin 183 of the detection lever 182. Since the detection lever 182 is biased clockwise, the pin 183 is brought into contact with the first or second detected part 561 or 562. Further, when the object 56 is moved in the X direction, the inclined connecting part 563 allows the pin 183 to be smoothly movable relatively between the first and second detected parts 561 and 562.

The second frame holder 82 is provided with a third detected part 81 as shown in FIG. 8C. The third detected part 81 is located at a higher position than the second detected part 562. The pin 183 of the detection lever 182 is brought into contact with the third detected part 81 when the second frame holder 82 is attached to the X-direction carriage 152.

Since the object 56 is provided on the sliding part 54, the location of the object 56 is shifted with movement of the moving arm 53 and the sliding part 54 in the X direction. More specifically, when the embroidery fame A is attached to the carriage 15, the moving arm 53 and the sliding part 54 are located at the first position to the left with respect to the first frame holder 50. In this case, the pin 183 of the detection lever 182 is brought into contact with the first detected part 561 as shown in FIG. 8A. On the other hand, when the embroidery fame B is attached to the carriage 15, the moving arm 53 and the sliding part 54 are located at the second position shifted rightward from the first position. In this case, the pin 183 of the detection lever 182 is brought into contact with the second detected part 562 as shown in FIG. 8B.

More specifically, when the embroidery frame A is attached to the carriage 15, the detection lever 182 is brought into contact with the first detected part 561 of the object 56, making a first angle, as shown in FIG. 8A. When the detection lever 182 is at the first angle, the detector 18 is assumed to take a first resistance value. The control device 31 detects the first resistance value as the resistance value of the detector 18. Based on the detection, the control device 31 detects the embroidery frame A as the type of embroidery frame W attached to the carriage 15.

On the other hand, when the embroidery frame B is attached to the carriage 15, the detection lever 182 is brought into contact with the second detected part 562 of the object 56, making a first angle, as shown in FIG. 8B. When the detection lever 182 is at the second angle, the detector 18 is assumed to take a second resistance value. The control device 31 detects the second resistance value as the resistance value of the detector 18. Based on the detection, the control device 31 detects the embroidery frame B as the type of embroidery frame W attached to the carriage 15.

Further, when the embroidery frame C is attached to the carriage 15, the detection lever 182 is brought into contact with the third detected part 81 of the second frame holder 82, making a third angle, as shown in FIG. 8C. When the detection lever 182 is at the third angle, the detector 18 is assumed to take a third resistance value. The control device 31 detects the third resistance value as the resistance value of the detector 18. Based on the detection, the control device 31 detects the embroidery frame C as the type of embroidery frame W attached to the carriage 15.

Further, when the embroidery frame W is not attached to the carriage 15 or when the embroidery frame W is incorrectly attached to the carriage 15, the detection lever 182 abuts against a stopper (not shown) mounted on the X-direction carriage 152 thereby to make a fourth angle differing from the first to third angles, although the condition is not shown in detail. When the detection lever 182 is at the fourth angle, the detector 18 is assumed to take a fourth resistance value. The control device 31 detects a fourth resistance value as the resistance value of the detector 18. Based on the detection, the control device 31 detects attachment of no embroidery frame W or incorrect attachment of the embroidery frame W.

The detector 18 thus detects the type of the embroidery frame W selectively attached to the carriage 15. The detector 18 also detects attachment of no embroidery frame W to the carriage 15. The number of embroidery frame types the detector 18 is capable of detecting should not be limited to three. Further, the detector 18 should not be limited to the potentiometer but may comprise a switch, a photo sensor, a magnetic sensor or a wireless tag.

The sewing machine 10 includes a projector 35 as shown in FIGS. 1 to 4. The projector 35 has a well-known configuration and may be an image projecting device including a liquid-crystal panel or a digital image projecting device including a digital micromirror device such as digital light processing (DLP® owned by Texas Instruments, Dallas), for example. The projector 35 is supported by a supporting device 40 and is connected to the control device 31 so as to be controlled by the control device 31 as shown in FIG. 4. The projector 35 projects an image onto the workpiece cloth held on the embroidery frame W as shown by alternate long and two short dashes lines in FIGS. 1 to 3. The embroidery frame W is eliminated in FIG. 3. A cable connecting the projector 35 to the control device 31 is not shown, either. The control device 31 serves as a control unit which controls image projection by the projector 35.

The support device 40 is provided on the left of the arm 13 and has a supporting member 41, a shaft member 42, two pairs of screw members 43 and a mounting member 44. The supporting member 41 is formed by bending a square bar material into a U-shape with an open right side as viewed in a plan view. The projector 35 is mounted to a distal end of the supporting member 41. The mounting member 44 is formed by bending, for example, a metal plate to a U-shape as viewed in a left side view and is fixed to the left side surface of the arm 13. The shaft member 42 is supported by the mounting member 44 in a position such that a shaft center thereof is directed in the up-down direction. The supporting member 41 has a distal end which is swingably supported by the shaft member 42. More specifically, the supporting member 41 is swingable with the shaft member serving as a fulcrum. The screw members 43 are inserted through two pairs of arc-shaped elongate holes 411 formed through the mounting member 44 from above and from below to be screwed into screw holes (not shown) formed in the vicinity of the distal end of the supporting member 41, respectively. As a result, the projector 35 is movable between a working position where the projector 35 is located at the front side of the needle bar case 20 and a retreat position where the supporting member 41 is swung so that the front of the needle bar case 20 is opened. The position of the projector 35 can be fixed by tightening the screw members 43.

The sewing machine 10 includes an operation panel 30 and the control device 31 as shown in FIG. 4. The operation panel 30 is mounted on the right of the arm 13 as shown in FIGS. 1 and 2. The operation panel 30 includes a liquid-crystal display 302 (hereinafter, “LCD”) having a touch panel 301 on a front thereof. The LCD 302 displays various keys, a plurality of embroidery patterns, thread information of needle threads set according to the respective needle bars, sewing conditions including thread tension and sewing speed, the names of functions required for a sewing operation, various pieces of information about sewing and the like. The user depresses locations which are on the touch panel 301 and correspond to various keys displayed by the LCD 302, respectively, with the result that instructing the functions, setting various sewing parameters and setting thread change can be performed.

The control device 31 functions as a control unit, a storage unit and a setting unit and is configured of a microcomputer including a CPU 311, a ROM 32 and a RAM 33 as shown in FIG. 4. The control device 31 is connected to the operation panel 30, the detector 18, the projector 35 and drive circuits 341, 342 and 343. The drive circuit 341 is connected to the X-axis motor 16. The drive circuit 342 is connected to the Y-axis motor 17. The drive circuit 343 is connected to the sewing machine motor 28.

The ROM 32 stores embroidery data 321, an embroidery data generating program 322, a sewing control program 323, a display control program 324, a projector control program 325, full thread information 326, frame information 327, projector information 328, projected image data 329 and the like. The embroidery data generating program 322 is provided for functioning the computer as various processing units to generate the embroidery data 321. The display control program 324 is provided for controlling the operation panel 30. The projector control program 325 is provided for controlling the projector 35 so that an image of embroidery pattern is projected. The full thread information 326 contains all pieces of information about a plurality of types of threads used for embroidery sewing and is inclusive of color information of the threads.

The frame information includes size data D representing a size of sewable regions corresponding to the embroidery frames A, B and C respectively and center position data P representing positions of sewable regions, as shown in FIG. 10. The center position data P indicates the center position of the sewable region in the case where the embroidery frames A, B and C are attached when the carriage 15 is located at a specified position. More specifically, the center position data P indicates a relative center position Pb (Xb, Yb) of a sewable region Qb of the embroidery frame B and a relative center position Pc (Xc, Yc) of a sewable region Qc of the embroidery frame C when a center position Pa (Xa, Ya) of a sewable region Qa of the embroidery frame A serves as a reference.

The specified position of the carriage 15 refers to a position where the Y-direction carriage 151 is located at the frontmost side within the Y-direction movable region and where the X-direction carriage 152 is located at the center position within the X-direction movable region. The carriages 15 shown in FIGS. 5 to 7 are located at the respective specified positions. The center position data P may be relative data with a central point of the needle hole of the needle plate 27 serving as a reference. Further, since the sewable region is rectangular in shape, for example, a position of one of four apexes may be used as the center position data P, instead of the center position of sewable region.

The projector information 328 is data regarding the projector 35 and more specifically, size data of projectable region L that is a maximum region onto which the projector 35 can project an image, and center position data of the projectable region L. In the embodiment, the size of the projectable region L of the projector 35 is set to a value larger than the sewable region Qa of the embroidery frame A expressed by, for example, 190 mm×140 mm in the respective X and Y directions. The projected image data 329 is data about an image of embroidery pattern to be projected onto the workpiece cloth by the projector 35. The above-described programs and data may be stored in another internal storage unit or an external storage unit such as a memory card (not shown).

The RAM 33 has storage areas for temporarily storing the above-described programs and data, various set values entered by the operation of the operation panel 30 and results of calculation performed by the control device 31. For example, the RAM 33 has a program storage area 331, an embroidery data storage area 332, a projected image storage area 333, a frame information storage area 334, a setting storage area 335 and the like as shown in FIG. 9. The program storage area 331 stores various programs read from the ROM or the like. The embroidery data storage area 332 stores data which serves as a reference when the color of the embroidery data or the like is set. Data of projected image selected by the operation of the operation panel 30 (the touch panel 301) is read from the ROM 32 and stored in the projected image storage area 333. The setting storage area 335 stores data of projection region of the projector 35 set based on the frame information stored in the frame information storage area 334.

The processing for control of the projector 35 performed by the control device 31 will now be described with reference to FIG. 12. Upon start of the processing (START), the control device 31 proceeds to step S11 to display a preview acknowledge button (not shown) on the LCD 302 of the operation panel 30 to detect whether or not a part of the touch panel 301 corresponding to the preview acknowledge button has been operated. When the preview acknowledge button (namely, the touch panel 301) has not been operated, the control device 31 stands by for operation of the preview acknowledge button (NO at step S11). When detecting operation of the preview acknowledge button (YES at step S11), the control device 31 proceeds to step S12 to move the carriage 15 to the specified position.

The user then attaches a desirable one of the embroidery frames A, B and C to the carriage 15. The control device 31 proceeds to step S13 to detect the type of the embroidery frame attached to the carriage 15, based on the result of detection by the detector 18. Thereafter, the control device 31 proceeds to step S14. At step S14, the control device 31 determines whether or not the type of the detected embroidery frame is the embroidery frame C. When the type of the detected embroidery frame is the embroidery frame C (YES at step S14), the control device 31 proceeds to step S15. The control device 31 sets the size of the projection region R by the projector 35 at step S15. More specifically, the control device 31 reads frame information about the embroidery frame C from the frame information stored in the ROM 32 and sets the size of projection region R according to the embroidery frame C, based on size data Dc in the sewable region Qc of the frame information 327. The size data Dc of the sewable region Qc is expressed as 25 mm×25 mm in the respective X and Y directions. As a result, the control device 31 sets the size of projection region R of the projector 35 to 25 mm×25 mm in the respective X and Y directions. More specifically, the control device 31 sets the size of projection region R to a size equal to the size of the sewable region Qc.

The control device 31 proceeds to step S16 when the type of embroidery frame is not the embroidery frame C (NO at step S14). At step S16, the control device 31 determines whether or not the type of detected embroidery frame is the embroidery frame B. The control device 31 proceeds to step S17 when the type of detected embroidery frame is the embroidery frame B (YES at step S16). The control device 31 sets the size of projection region R by the projector 35 at step S17. More specifically, the control device 31 reads frame information corresponding to the embroidery frame B from the frame information 327 of the ROM 32 and sets the size of projection region R by the projector 35, based on size data Db of the sewable region Qb in the frame information 327. The size data Db of the sewable region Qb is expressed as 60 mm×40 mm in the respective X and Y directions. As a result, the control device 31 sets the size of projection region R of the projector 35 to 60 mm×40 mm in the respective X and Y directions. More specifically, the control device 31 sets the size of projection region R to a size equal to the size of the sewable region Qb.

The control device 31 proceeds to step S18 when the type of detected embroidery frame is not the embroidery frame B (NO at step S16). At step S18, the control device 31 determines whether or not the type of the detected embroidery frame is the embroidery frame A. The control device 31 proceeds to step S19 when the type of the detected embroidery frame is the embroidery frame A. The control device 31 sets the size of projection region R by the projector 35 at step S19. More specifically, the control device 31 reads frame information corresponding to the embroidery frame A from the frame information 327 of the ROM 32 and sets the size of projection region R by the projector 35 based on size data Da of sewable area Qa in the frame information 327. The size data Da of the sewable region Qa is expressed as 180 mm×130 mm in the respective X and Y directions. As a result, the control device 31 sets the size of projection region R of the projector 35 to 180 mm×130 mm in the respective X and Y directions. More specifically, the control device 31 sets the size of projection region R to a size equal to the size of the sewable region Qa.

On the other hand, when any one of embroidery frames A, B and C is incorrectly attached to the carriage 15, the control device 31 proceeds to step S20 where the control device 31 displays the message, “embroidery frame cannot be detected” on the LCD 302, encouraging the user to reattach the embroidery frame. Subsequently, the control device 31 returns to step S13.

The control device 31 proceeds to step S21 after having set the size of projection region R at any one of steps S15, S17 and S19. The size data of projection region R set at any one of steps S15, S17 and S19 is stored in the setting storage area 335 of the RAM 33.

At step S21, the control device 31 calculates a center position Pr of projection region R from the size of projection region R and sets the projection region R so that the center position Pr corresponds with the center point P of sewable region Q. More specifically, when the embroidery frame A is attached to the carriage 15, the control device 31 sets the projection region R so that the center position Pr of projection region R corresponds with the center position Pa of sewable region Qa of embroidery frame A, as shown in FIG. 13A. When the embroidery frame B is attached to the carriage 15, the control device 31 sets the projection region R so that the center position Pr of projection region R corresponds with the center position Pb of sewable region Qb of embroidery frame B, as shown in FIG. 14A. When the embroidery frame C is attached to the carriage 15, the control device 31 sets the projection region R so that the center position Pr of projection region R corresponds with the center position Pc of sewable region Qc of embroidery frame C, as shown in FIG. 15A. The center position Pr of projection region R set at step S21 is stored in the setting storage area 335 of RAM 33.

The control device 31 then controls the projector 35 so that an outline of projection region R set at any one of steps S15, S17 and S19 is projected as an image representing the size of sewable region Q. More specifically, when the embroidery frame A is attached to the carriage 15, the control device 31 controls the projector 35 so that an outline Ka of projection region R is projected as the image representing the sewable region Qa, as shown in FIG. 13A. When the embroidery frame B is attached to the carriage 15, the control device 31 controls the projector 35 so that an outline Kb of projection region R is projected as the image representing the sewable region Qb, as shown in FIG. 14A. When the embroidery frame C is attached to the carriage 15, the control device 31 controls the projector 35 so that an outline Kc of projection region R is projected as the image representing the sewable region Qc, as shown in FIG. 15A. Although the outlines Ka, Kb and Kc are marked with scales Ma, Mb and Mc as shown in FIGS. 13A to 15B, respectively, the scales Ma, Mb and Mc may not be attached to the outlines Ka, Kb and Kc.

Subsequently, the control device 31 proceeds to step S23 to display a plurality of types of embroidery patterns on the LCD 302 of the operation panel 30. When the user then operates the touch panel 301 to select a desirable embroidery pattern, the control device 31 proceeds to step S24. When the embroidery frame A is attached to the carriage 15, the control device 31 controls the projector 35 so that an image representing the embroidery pattern J selected by the user is projected while the center position of the embroidery pattern J corresponds with the center position of the sewable region Qa, as shown in FIG. 13B. When the embroidery frame B is attached to the carriage 15, the control device 31 controls the projector 35 so that an image representing the embroidery pattern J selected by the user is projected while the center position of the embroidery pattern J corresponds with the center position of the sewable region Qb, as shown in FIG. 14B. When the embroidery frame C is attached to the carriage 15, the control device 31 controls the projector 35 so that an image representing the embroidery pattern J selected by the user is projected while the center position of the embroidery pattern J corresponds with the center position of the sewable region Qc, as shown in FIG. 15B. The control device 31 thereafter ends the processing (END).

According to the above-described configuration, the control device 31 sets the projection region R of the projector 35 based on the frame information 327 of embroidery frame W attached to the carriage 15. More specifically, the control device 31 changes the projection region R according to the embroidery frame W attached to the carriage 15. Accordingly, the projector 35 can appropriately project an image onto the workpiece cloth held on the embroidery frame W even when the embroidery frames W differ in size and shape. As a result, the user can correctly confirm a scheduled sewing position of embroidery pattern before actual embroidery sewing based on the image projected from the projector 35.

The frame information 327 includes the size data D representing the size of sewable region Q set inside the embroidery frame W and the position data P representing the position of sewable region Q with the embroidery frame W being attached to carriage 15. The control device 31 sets the projection region R based on the size data D and the position data P. According to this, the projector 35 can project an image with an optimum size onto a correct position on the workpiece cloth held on the embroidery frame W without positional shift.

The image projected from the projector 35 includes at least the image J representing the desired embroidery pattern selected by the user or the outline K (Ka to Kc) representing the sewable region Q corresponding to the embroidery frame W attached to the carriage 15. According to this, the user can confirm an image of sewn-up pattern when viewing the image of embroidery pattern projected onto the workpiece cloth. Further, the size and position of sewable region Q of the embroidery frame W can also be confirmed correctly.

The foregoing embodiment should not be restrictive but may be modified or expanded. In a modified form, although the sewing machine 10 is a multi-needle sewing machine provided with six needle bars, the sewing machine 10 may be an embroidering lock stitch sewing machine provided with a single needle bar.

The foregoing description and drawings are merely illustrative of the present disclosure and are not to be construed in a limiting sense. Various changes and modifications will become apparent to those of ordinary skill in the art. All such changes and modifications are seen to fall within the scope of the appended claims. 

We claim:
 1. A sewing machine comprising: a plurality of types of embroidery frames having respective holding parts which hold a workpiece cloth, the holding parts having forms differing from one type of embroidery frame to another; a carriage to which one of the embroidery frames is selectively attached, the carriage being configured to transfer the embroidery frame attached thereto; a projector configured to project an image onto the workpiece cloth held on the holding part of the embroidery frame attached to the carriage; a detector configured to detect a type of the embroidery frame attached to the carriage; a storage unit configured to store frame information set for every type of embroidery frame; a setting unit configured to read the frame information from the storage unit according to a result of detection by the detector and to set a projection region for an image to be projected by the projector, based on the frame information; and a control unit configured to control the projector so that the projector projects the image onto the projection region set by the setting unit.
 2. The sewing machine according to claim 1, wherein: the frame information includes at least size data representing a size of a sewable region set inside each holding part and position data representing a position of the sewable region in an attached state where the embroidery frame is attached to the carriage; and the setting unit is configured to set the projection region based on the size data and the position data.
 3. The sewing machine according to claim 2, wherein the image to be projected by the projector includes at least an image representing a desirable embroidery pattern selected by a user or an image representing the sewable region.
 4. The sewing machine according to claim 3, wherein the control unit is configured to control the projector so that the projector projects an outline of the projection region as the image representing the sewable region. 